when president obama and mitt romney step on the stage behind me tomorrow night, it's going to be the first time they've seen each other face to face in nearly five years. to give you a sense of just how crucial his performance is, romney aids brought podiums into his hotel conference room late today to help him simulate the real thing. fueling up for an afternoon study session today. >> governor, are you ready for tomorrow? >> i'm getting there. >> reporter: he's been practicing 12kizingers to sharp critique the president, may have gotten help from an unlikely ally. vice president joe biden today. >> hugh they can justify raising taxes on the middle class has been buried the last four years. how in lord's name can they justify raising their taxes. >> the romney campaign seized on that comment. arguing the president's policies have hurt the middle class. taking a breather from his preparations outside las vegas today. he visited the hoover dam. >> it's spectacular and i've never seen it before. >> reporter: aides say he's been calling his family to unwind each night. surrogates on bot